Full Breakdown
New World Screwworm Reappears in the United States
6/15/2026, 6:07:42 AM
Background and Context
The New World screwworm (NWS) was declared eradicated from the United States in 1966 after a decades-long sterile-fly program. Beginning in 2023, the parasite moved north from Central America into Mexico, where more than 28,000 cases have been recorded. Warmer, more humid conditions—linked by scientists to climate change—have expanded the fly’s viable habitat, allowing it to survive farther north than in previous decades.
Key Figures and Organizations
- Brooke Rollins, U.S. Secretary of Agriculture (USDA).
- Greg Abbott, Governor of Texas, who issued a statewide disaster declaration.
- Sid Miller, Texas Agriculture Commissioner.
- Dawn Buckingham, Texas Land Commissioner.
- Texas Animal Health Commission and USDA Animal and Plant Health Inspection Service (APHIS), leading surveillance, quarantine, and sterile-fly releases.
Data and Statistics
- USDA reports 12 confirmed NWS infestations (11 in Texas, 1 in New Mexico).
- Earlier counts ranged from six to nine cases, reflecting rapid updates.
- Texas cattle production generates roughly $41 billion annually.
- USDA has earmarked over $1 billion for the response, including a $750 million plant capable of producing up to 300 million sterile flies per week.
- A 12-mile quarantine zone surrounds each confirmed case; Canada has temporarily halted livestock imports from Texas.
Why It Matters: Economic and Environmental Impact
The parasite threatens Texas’s livestock and wildlife, with potential to depress an already tight beef supply. Experts caution that a large-scale outbreak could pressure beef prices, though most agree current case numbers are insufficient to cause immediate price spikes. Climate-driven expansion of suitable habitat raises the risk of further spread into additional U.S. states and Canada.
Official Statements and Responses
Governor Abbott described the summer as “extraordinarily challenging” and emphasized the deployment of millions of sterile male flies to break the reproductive cycle. USDA Secretary Rollins framed the outbreak as a national emergency, noting the need for 500 million sterile flies weekly to achieve eradication. The USDA reiterated that the parasite does not affect meat safety.
Criticism and Opposition
Democratic senators have questioned USDA staffing cuts, citing a letter that highlighted a 20 % drop in Animal Plant and Health Inspection Service personnel in many counties. Rep. Ted Lieu blamed the Trump administration for the resurgence, stating the administration had been in office “over 500 days.” Texas Agriculture Commissioner Sid Miller criticized the USDA for relying on a “partial solution” and for a perceived delay in deploying all available control tools.
On-the-Ground Reports
The first U.S. case was a three-week-old calf in Zavala County, Texas, followed by additional cattle, a goat in Edwards County, and a dog in Lea County, New Mexico. Rancher Stephen Diebel reported heightened vigilance, including injections to prevent infestation and careful wound management.
Conflicting Reports and Gaps
Case counts vary across sources (six, seven, nine, twelve), reflecting evolving surveillance. Rollins has alleged that illegal cattle trafficking by Mexican cartels contributed to the spread, yet USDA officials have not released direct evidence linking specific cases to such movements. The precise pathway of the initial U.S. introductions remains unconfirmed.
Verbatim Quotes
- “He couldn't be happier. He's bouncing around the pasture,” — Brooke Rollins, U.S. Secretary of Agriculture
- “People moving north to America, bringing their livestock with them, the Mexican cartels with the illicit cattle traffic, we knew it was coming,” — Brooke Rollins, U.S. Secretary of Agriculture
- “For months, the screwworm has advanced rapidly through Mexico in spite of the USDA’s existing gameplan,” — Sid Miller, Texas Agriculture Commissioner
- “The life cycle of a screwworm is about 14 to 54 days, depending on temperature and humidity. The Trump administration has been in office for over 500 days,” — Ted Lieu, U.S. Representative
- “This is not a food safety issue — the U.S. food supply remains safe,” — U.S. Department of Agriculture
What’s Next
A new sterile-fly production facility at Moore Air Base is slated for completion in November 2027, after which weekly releases could reach 500 million flies. USDA and Texas officials will maintain quarantine zones, expand surveillance, and operate a 24-hour reporting hotline as they aim to contain the outbreak before winter reduces fly populations.
